Yttrium-iron-garnet, often referred to as "YIG", is a synthetic ferrimagnetic material with the garnet crystal structure which may be represented by the formula Y.sub.3 Fe.sub.5 O.sub.12. It is often used in microwave ferrite devices because of its very narrow ferromagnetic resonance absorption line. This material, and some of its uses, are discussed in U.S. Pat. Nos. 5,192,928, 5,189,383, 4,516,096, 4,420,731, 4,273,610, 4,060,448, and the like. The disclosure of each of these United States patents is hereby incorporated by reference into this specification.
The hysteresis loop of yttrium-iron-garnet devices is the closed curve followed by such material on a graph of a driven variable (such as magentic flux density or electric polarization) versus the driving variable (such as magnetic field or electric field).
It is an object of this invention to produce an yttrium-iron-garnet material with a larger hysteresis loop.
It is another object of this invention to provide an yttrium-iron-garnet material which is more homogeneous, purer, finer-grained, and cheaper to prepare than prior art materials.